"You're Repulsive!"Teaching VSEPR in a Not-So-Elegant WayRobert S. H. LiuValence shell electron pair repulsive (VSEPR) interaction is an important concept particularly in discussing structural properties of molecules. In this article we showed five organic examples not commonly associated with VSEPR but yet all involving repulsive interactions of valence electrons, which provides ready explanations for altered chemical reactivity and spectroscopic properties of organic compounds. The ready catchy phrase Youre Repulsive! is the common thread used throughout these five examples.Liu, Robert S. H. J. Chem. Educ.2005, 82, 558.

Mechanisms of Reactions |

UV-Vis Spectroscopy |

Reactions |

Addition Reactions |

Electrophilic Substitution

The Evolution of a Green Chemistry Laboratory Experiment: Greener Brominations of StilbeneLallie C. McKenzie, Lauren M. Huffman, and James E. HutchisonWe describe two new greener alkene bromination reactions that offer enhanced laboratory safety and convey important green chemistry concepts, in addition to illustrating the chemistry of alkenes. The two alternative reactions, one involving pyridinium tribromide and a second using hydrogen peroxide and hydrobromic acid, are compared to the traditional bromination of stilbene through the application of green metrics, including atom economy, percent experimental atom economy, E factor, and effective mass yield.McKenzie, Lallie C.; Huffman, Lauren M.; Hutchison, James E. J. Chem. Educ.2005, 82, 306.

Synthesis |

Green Chemistry |

Aromatic Compounds |

Addition Reactions |

Alkenes

A Substitute for “Bromine in Carbon Tetrachloride”Joshua M. Daley and Robert G. LandoltBenzotrifluoride (BTF) is a suitable solvent substitute for carbon tetrachloride in experiments requiring application of bromine (Br2) in free radical or addition reactions with organic substrates. A 1 M solution of Br2 in BTF may be used to distinguish hydrocarbons based on the ease of abstraction of hydrogen atoms in thermally or light-induced free radical substitutions. Efficacy of minimization of solvent use, by aliquot addition to neat samples, has been established.Daley, Joshua M.; Landolt, Robert G. J. Chem. Educ.2005, 82, 120.

Alkenes |

Free Radicals |

Green Chemistry |

Qualitative Analysis |

Reactions

Organic lecture demonstrationsSilversmith, Ernest F.Organic chemistry may not be known for its spectacular, attention getting chemical reactions. Nevertheless, this author describes a few organic chemistry reactions that put points across and generate interest. This article provides a convenient sources of demonstrations and urges others to add to the collection. Demonstrations concerning: carbohydrates, spectroscopy, proteins, amines, carbohydrates, carboxylic acids, and much more.Silversmith, Ernest F. J. Chem. Educ.1988, 65, 70.